Naturalists at Large Soil composition Slide Show

2. 4th Grade
Springville, Utah

3. Where does soil come from?
•Rocks
•Minerals
•Organic Matter

5. o
A
TOP SOIL
E
B
SUBSOIL
C
R

7. Sagebrush-Cold Desert

8. What are the main components of
soil?
• Mineral Matter
• Air
• Water
• Organic Matter

9. SOIL COMPONENTS
idealized soil
25%
AIR FILLED PORES
25 %
WATER FILLED PORES
50 %
SOIL SOLIDS

10. Soil Components (volume basis)

11. Note: clays are microscopic in size !

12. Soil separate particle diameter (mm)
____________________________
Sand . . . . . . . . . 2.0 - 0.05
Silt . . . . . . . . . . 0.05 - 0.002
Clay . . . . . . . . . . <0.002
SAND
SILT CLAY

13. Clay minerals
photographed
with an electron
Microscope.
Note: they are plate
or flake like and
are stacked on top
of each other.
They are electrically
charged and act like
magnets that attract
and hold plant
nutrients.

16. What causes soil erosion?
Water
Wind
No Vegetation

25. How did the Canyon Lands
of Utah form?

32. What are the FACTORS
that make SOIL?
TIME
1000’S TO 10,000’S OF YEARS
LAY OF THE LAND
TOPOGRAPHY
LIVING ORGANISMS
ANIMALS AND PLANTS
CLIMATE
HOT/COLD, WIND/RAIN
PARENT MATERIAL
ROCKS AND MINERALS

33. Physical land features

34. What are some practices
Of
SOIL
CONSERVATION?
Terracing
Strip Cropping
Contour Plowing
Tilling
Wind Breaks
Ground Covers

47. Internet Sites
• http://www.tx.nrcs.usda.gov/class/sammy.htm